1. Field of the Invention
This invention relates to a fishing reel, and more particularly to a fishing reel provided with a line length measuring device to determine unwound amount and wound amount of the fishing line based on the number of spool revolutions.
2. Description of the Prior Art
Recent fishing reels are provided with a mechanism to measure the length of fishing line unwound or wound onto a spool so that the line accurately reaches the shelf where fish are gathering and that the distance to the fishing point in casting is indicated.
Conventionally, the unwound or wound amount of fishing line has been measured, as disclosed in the Japanese Application Laid-open No. 57-155931 for example, by detecting the spool rotations with a sensor and counting the pulse signal generated at the sensor once per spool rotation The counted value is sent to a microcomputer for each operation cycle to operate the line length, and the operation result is output to the display unit for line length indication.
However, for a conventional line length measuring device as described above, line winding diameter at the spool decreases as the line is unwound and increases as the line is wound, resulting in varying unwound or wound length per spool rotation. Accordingly, the real line length cannot be obtained by multiplying the counted pulses generated once per rotation by the line length for one rotation of the spool. This causes a large difference between the indicated value and the actual unwound or wound length. In addition, when a fishing line of different diameter or different type is used, increase or decrease ratio of the line winding diameter for unwinding or winding changes and the real line length cannot be determined.